Dovetail and box joints are well known methods for joining the side panels of wooden boxes or drawers to their front and back panels. This is accomplished by the use of interlocking joints cut into the ends of each panel where one joins to the other. The interlocking joints are ultimately held together by adhesives.
In ancient times, dovetail and box joints were laboriously cut by hand. Later, with the invention of the router, they were cut by a rotating cutting tool on a router. Cuts were evenly spaced on the ends of wood panels by employing templates which guided the cutter on a hand held router.
With the development of router tables, the router was able to be mounted in a fixed position. Now instead of the router being moved through a wooden panel or workpiece, the workpiece is moved into a stationary cutting tool.
The current state of the art for cutting dovetail and box joints includes jig systems that when secured to a router table help to guide a workpiece into the cutting tool of a router mounted into the table. The workpiece is guided against one side of a fence, which is part of the jig systems, as it is pushed into the cutting tool. The current technologies guide the fence after each cut. Subsequent cuts are then made at very precise locations equidistant from each other along the edge of the workpiece.
Currently, the indexing of the fence is controlled by two technologies. One method uses a lead screw which, when rotated, moves the fence away from the cutter a measured distance. The other technology utilizes a fence attached to one of two racks which face each other. They are held in position by meshing of interlocking teeth and moved a measured distance before each new cut.
These technologies, although improvements, create several problems. For instance, the movement of a fence by means of either racks or lead screws is controlled by templates or scales with graduated markings. As such, an operator must choose the correct scale or template and then precisely line up the graduations with a cursor after each cut is made with the router bit.
Another disadvantage of the present technologies lies in the problem created by the fact that the workpiece can only be presented to the cutting tool from one side of a fence. This is a serious shortcoming because to make a proper dovetail joint, both ends of the workpiece must be cut from the same relative starting point. When both ends of a workpiece are cut on the same side of the fence, as is the case with the current systems, the starting point for a series of joint cuts made on the ends of a drawer's front and/or back panel will be at different places. This results in a misalignment of joints when the drawer is assembled.
A still further disadvantage of the current systems lies in attempts to correct the problem presented by using only one side of a fence for guiding a workpiece. As stated earlier, alignment of the joints is difficult when using only one side of the fence. To overcome this problem, the current systems center the joint cuts on the workpiece. For instance, dovetail cuts are measured from the center of a workpiece out to both ends. As a result, this method restricts the widths of the drawer sides to only those which would permit dovetail cuts to fit completely within the confines of the workpiece. If the dovetail cuts do not fit completely into the confines of a drawer width then a hole can be seen on either end of the drawer side. Clearly, a hole that is visible on the top surface of a drawer side is unacceptable especially in a piece of furniture where fine workmanship is expected.
Another disadvantage of the present technologies includes the use of a plurality of fixed templates that require a specific cutting tool height. However, the accuracy of these systems is decreased by the difficulty encountered in accurately repeating the required placement height of the cutting tool in the router table.
A still further disadvantage of the present technologies includes the inability to use the exhaust port that exists in router table models that are currently available. As such, sawdust collection is not easily accomplished.
Accordingly, what is needed is a jig system that eliminates the cosmetic restrictions placed on the width of a workpiece wherein only certain widths are acceptable; the necessity to rely on one's ability to visually line up graduations on a cursor after each cutting; the plethora of single purpose templates and the inherent inaccuracy due to the difficulty of placing the cutting tool at an exact height in the router table.